Invasive assessment of the coronary microcirculation using the index of microcirculatory resistance: Description and validation of an animal model

The index of microcirculatory resistance (IMR) provides quantitative, invasive, and real-time assessment of coronary microcirculation status. The primary aim of this study was to validate the assessment of IMR in a large animal model, and the secondary aim was to compare two doses of intracoronary papaverine, 5 and 10 mg, for induction of maximal hyperemia and its evolution over time. Measurements of IMR were performed in eight pigs. Mean distal...